Quantum dots are widely used due to their characteristics of excellent luminance and light absorption, purity color, and color saturation. The application range includes light sensors, single electron transistors, memories, catalysts, or quantum calculation. In the biomedical engineering, for example, the quantum dots can be manufactured to be any kinds of fluorescent labels, gene barcodes and protein barcodes applied for biological inspection, comparison symbols of magnetic resonance image and positron emission tomography used in human body, and evaluation of cancer diagnosis and medication.
Currently, the graphene quantum dots are produced by chemical material synthesis. However, the chemical material synthesis method needs several complex procedures which result in consuming time, and also, the graphene quantum dots synthesized by the chemical synthesis should take any environmental conditions into consideration. Besides, the chemical material brings the pollutions to environments easily, and therefore, the problem of synthesizing graphene quantum dots with non-pollution, simple procedure, and low cost needs to be solved.